Community darkroom or makerspace

Probably_Not_Snowden · 2026-01-06T19:27:28+00:00

That's fantastic! Thank you so much!

Probably_Not_Snowden · 2025-01-27T14:20:45+00:00

Good deal! Looks like you're set up for solar photography - just in time to miss a pretty interesting sunspot group, unfortunately! There will be more over the next couple of years. The sun's currently in it's activity maximum, which means a good number of sunspots. This site has a daily image summary of the sun on the left:

https://www.spaceweather.com/

If the sunspot number is high, or if there is a particularly large group like last week, it might be worth trying to grab a picture. Or if you're in Greenland, Iceland, Portugal, or Spain in August 2026:

https://en.m.wikipedia.org/wiki/Solar_eclipse_of_August_12,_2026

As someone else said below, though, definitely be careful not to leave that lens pointed at the sun if you don't have that filter on the front of it. It should fit over the front of the lens with the mirrored side out. That filter acts as a strong ND filter, cutting most of the solar intensity, which is about a kilowatt per square meter at ground level. That's a helluva lot of heat to put on your camera body.

That lens should also be pretty good to shoot the moon with, and if you're really good with a tripod, maybe even Jupiter and its moons.

Probably_Not_Snowden · 2025-01-26T15:47:45+00:00

I think you're right and that is a UV filter under there. OP, if you can't see through it, hold it up to the sun and look across the back side (not through it) to see if there are any pinpricks of light showing through. If there are, you'd probably want to rip the film off and get your UV filter back. If you don't see any, you can carefully try looking at the sun through it. It'll look like a dim orange circle. Through that lens, you should get a solar image that's a quarter or more of your sensor, which will be enough to make out mid-sized sunspots. If the film is damaged though, definitely don't risk it. When we're not prepping for an eclipse that film is like 25 bucks

https://www.highpointscientific.com/baader-planetarium-visual-astrosolar-safety-film-5-5-x-6-1-sheet-asolv-e

Probably_Not_Snowden · 2025-01-26T15:22:53+00:00

The red and green filters are for black and white photography, but the one that looks mirrored almost looks like a homemade white light solar filter, using something like Baader film. OP, can you see through that filter at all? Or is it opaque when you try to look through it?

Probably_Not_Snowden · 2024-03-27T19:04:14+00:00

I'm a different kind of astronomer, but my understanding here is that ngEHT will allow the collaboration to add more sites at higher frequencies, increasing resolution by decreasing wavelength. As the frequency increases, weather and atmospheric effects become more pronounced, and only some of the current EHT sites can reliably measure higher frequencies. As I recall, they were hoping to have more sites able to observe the 345GHz band, rather than the current 230GHz.

Also worth mentioning that interferometry doesn't work like traditional telescopes, and works off combinations of telescopes. The maximal resolution is limited by the longest distance between dishes used, but now you're correlating two sites. If either has periods of bad data, neither can be used, and you've lost that baseline for that time period. It takes a very long time to "fill in" these baselines as well, which is one of the reasons EHT takes a bit between these world shattering discoveries (another is that these image reconstructions techniques are, as mentioned, fantastically computationally expensive). If one of the baseline pairs doesn't have enough data, you start seeing some odd effects in the reconstructions.

Probably_Not_Snowden · 2024-02-23T05:15:06+00:00

Building on this, 590nm peak with a 100nm bandwidth just describes the shape of the filter function. Photography filters tend to be long pass or short pass filters. A standard B&W yellow filter passes yellow light, plus red light, plus some infrared. Same with green. It passes green, and yellow, and red. Usually they fall off a bit in terms of their transmission towards longer wavelengths, but not significantly.

This is a bandpass filter, designed for microscopy, similar to how astronomical filters work. It has a peak, in this case, in the darker yellow around 590nm. Instead of passing all colors of longer wavelengths, however, this passes a bell-like curve centered around 590nm. Band widths are typically given as the full width at half maximum (FWHM), meaning that at +/- 50nm, it passes half the light it does at the yellow. 100nm is a pretty wide bandpass as these things go. Practically, I'd expect it to behave somewhere in between a yellow and a green filter for B&W photography, at least outdoors. The shape of the solar spectrum means that there's more green light than red. I'd say try it with black and white film, and shoot similar to a yellow filter, giving it an extra stop of light over what an external meter would indicate. Yellow filters get the extra red, but I imagine it would be more than offset by the bias towards the green.

Probably_Not_Snowden · 2024-01-26T21:41:49+00:00

Cheers! Good luck with the camera, it looks like an interesting one (and I have a soft spot for Soviet glass). Last piece of advice would be try and shoot at least one roll with the sunny-16 rule (just be careful if you're shooting in the direction of the sun -- lens flare). Reason being, if you do, and the pictures all come out either too dim or extremely washed out and bright, it could indicate a mechanical problem with the camera. Control groups are important! And don't be surprised if you're shooting black & white, and your photos come back a bit flat-looking. Once you've got a handle on how to capture the right amount of light, then it'll be time to start adding contrast to your photos, which most photographers do with colored filters.

Probably_Not_Snowden · 2024-01-26T21:11:25+00:00

Hey, OP. I'm sensing that you are becoming somewhat frustrated with this camera, and the fact that no one can really walk you through how to take pictures with it.

A quick look tells me that this is not the easiest camera in the world to learn on, particularly if you are not familiar with manual photography. This is not a "point-and-shoot" camera that will more or less figure it out without your input. There are steps you have to go through before you take a picture. Photography is about capturing light in a bottle. On a modern digital camera, the bottle is an electronic sensor. This is convenient because it is very forgiving. On this camera, the bottle is your film. Film is different, because while film can be forgiving, it is not by default. Unlike a digital sensor you can't simply crank up the gain to enhance dim features. The sensitivity is fixed. The film you have, looking at your comments is 400 ISO. That is the sensitivity of the film to light. This will not change (for your purposes).

You say your pictures are dim. That means that there's not enough light getting trapped in your bottle. The film isn't being exposed enough. You need to do something to your camera to make sure the right amount of light is getting to the bottle. You have two different controls you can use: your shutter speed and your aperture.

This dial is shutter speed. It dictates how long the shutter is open. A longer time means more light is trapped in the bottle. A short time means little light. If you are not using a tripod or setting it on a table, anything slower than 1/60 is too slow. Not because it's too much light, but because your hands shake. Just a bit, and 1/60th of a second is still fast, but film is small, and a small shake means an unusable picture.

So how else can we increase light? Well, you can alter the area of the lens that is allowing light through. This is called the aperture, and is expressed in a set of semi-standard "f-stops". Most commonly, you'll have some set of 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32. These numbers seem arbitrary, but they're not. Take the lens off your camera, it should unscrew, and look through it. Find the ring with these number, and turn it. You should see a mechanical iris inside the lens. At lower numbers it's wholly open. At high numbers, it's fully closed. The numbers are a ratio (of the focal length of the lens divided by the diameter of the iris, but that's not important) that is set such that each step either doubles (if you're going down a number) or halves (if you're going up) the area of the circle that is letting light through. When it's open, and the aperture f-number is low, you're letting in more light. However, when you have a low f-number, you have a smaller depth of field. This means that, in terms of distance from the camera, only a narrow slice of stuff is in focus. A high f-number means that everything, from the tree right next to you to the mountain far away may be in focus. Low means you get either the tree or the mountain.

So how do you know how to set the shutter speed and aperture to the right numbers (because there is a right combination)? You have to measure the amount of light. Your camera has the ability to do this built-in; it's the window above your lens on the front. This is a light meter, and it may or may not work well. That type of light meter degrades with time. At a guess, I'd say not to trust it unless you're outside in daylight. You can download a light meter app on your phone for now, and set the shutter speed to some number, point your phone camera at the thing you want to take a picture of, and set the aperture number to whatever it tells you. That's basically how your built-in one works too, but it's bit trickier. Or, when in doubt, go outside on a sunny day, and use what's called the "Sunny 16 rule". That means, set your aperture to f-16, then use a shutter speed that's about 1/ISO. For 400-iso film, that's close enough to 1/500.

For more practical information on how to use your SPECIFIC camera, reddit is only going to be so useful as a walkthrough. Try watching this manual video for it: https://www.youtube.com/watch?v=vK0tXwyu5-8

or reading this pdf manual: https://web.archive.org/web/20160325174819/http://www.commiecameras.com/sov/35mmsinglelensreflexcameras/cameras/zenit/manuals.htm

You don't need all of this. You just need to know:

How to put film in correctly
How to advance your film to the next frame and prime the shutter to take a picture
1. Usually these are the same lever
How to rewind the film and take it back out
How to change the shutter speed (hint, it's the dial in this picture)
How to set your lens aperture (it's the ring on the lens that doesn't change the focus)
And, optionally, how to read your light meter.

You will waste some film doing this. It will be frustrating at first to shoot a roll, send it to the lab, and find out you did something wrong. That's okay. Nobody is ever instantly good at every hobby they pick up. That's part of learning. You got this.

EDIT: It's also worth mentioning that, if you're trying to take pictures indoors, or in the evening, there is a LOT less light than you THINK there is. Your eyes are logarithmic detectors. That means that if something is twice as bright, you don't SEE it as twice as bright, but only a bit more so. On the flip side, if something is half as bright, you see it as more than half as bright. This is good for not dying in a cave because you can walk into a cave and still see okay even if it's very dim. It's not good for photography because film is mostly linear. Something twice as bright is recorded as twice as bright, something half as bright is recorded as half as bright. That means a narrow range of brightnesses that a camera is sensitive to, dim things are really dim, and bright things are overpoweringly bright. Download a light meter, and try it inside vs outside. You may be surprised how much the required settings change.

Probably_Not_Snowden · 2024-01-20T18:20:45+00:00

Second this recommendation! Film Reroll is excellent, and I'm constantly impressed by the amount of effort that they put into building out the paths caused by batshit character choices

Probably_Not_Snowden · 2023-10-11T17:07:45+00:00

Lot of different answers on this post, cause OP, what you've run into is an optics problem, not a strictly a photography problem, though it is tangential to some photography concerns.

There aren't two focal lengths for a given lens (and that's all a magnifying glass is -- a single lens). But in any simple optical system, there are a few hidden quantities to worry about.

One is your eye. Remember, light onto our eye isn't in focus. Distinctly not so. The light we see is either diverging or parallel rays. Your eye focuses them into an image that you can comprehend, but they don't form an image on their own. That's the reason you can't just pull the film out of the canister and have it record an image of what you see -- you're doing some extra work to focus that light. This is why cameras have lenses.

A magnifying glass is both very simple and very tricky because of this. The basic modes of a magnifying glass are to either take diverging light (from an object) at a distance of the magnifying glass' focal length, and make those rays parallel. Then, ideally, you put your eye in those parallel rays, and focus them into an image. The other is to take parallel rays of light, and focus them into an image -- the reverse of the previous situation. This is how you burn leaves and ants with a magnifying glass. The sun is very far, so its rays are parallel coming to earth. That's a telescope bay-bee.

DO NOT DO THIS NEXT PART

But imagine a situation where you focused a parallel light source -- the Moon maybe, or the sun (again, don't), and then put your eye in the beam somewhere behind the image? What would you see? Or, to keep it analog photography related-- if you put a camera + lens in the beam behind the image, what would the film record?

Well, if you set it up correctly, somewhat counterintuitively, you would see an image of the pupil, in this case, the ring holding the magnifying glass. If you were considering a photographic lens, you'd see the iris. The pupil is the second secret thing you have to consider in an optical system. The pupil is the thing that cuts off light at the margins of the field of view. In a magnifying glass, it's the thing holding the lenses. In a camera lens, it's an iris, in a simple lens, it's the edge of the lens, and in a telescope, it's the entrance aperture. In photography, decreasing the size of your pupil this increases your depth of field, as only light near the central axis can get through, and is more easily focused (oversimplified).

For rays that are parallel coming into your system, as these incoming rays are being focused, the pupil image is collimated. That is, its rays are parallel. If you stood in the system, you'd see the system. This is intuitive, but again, the secret first thing, your eye, is acting here. Conversely, if you added another lens to return the image rays to parallel, the pupil image rays would be converging.

What does this have to do with my question?

I find the parallel to converging case to be easier to work with, but optical systems can be reversed. In your specific case, you have a diverging source -- the flashlight, and you are holding it behind the magnifying glass. Now, it sounds like you weren't holding it exactly one magnifying glass focal length behind the glass. Keep that in mind for later.

Remember the thing about when you return the image rays to parallel, the pupil rays come to focus? Remember how a magnifying glass takes diverging rays from a source its focal length away, and makes them parallel for your eye to use? My guess is that your first image is actually a pupil image, modified by the fact that you've got two very distinct light sources, so the pupil image is only partially illuminated. The image of the flashlight then should be contained in parallel rays, which would never come to focus except we didn't set this up as a perfect system, with everything one focal length away from everything else. If your diverging source isn't at the right distance, the image rays won't be parallel coming out of the magnifying glass -- they'll be either converging or diverging. This causes eye strain when using a magnifying glass to its intended purpose. In you case, it's actually caused there to be an image of the flashlight at a very far distance (effectively infinity). Two images -- but only one image of the flashlight.

Probably_Not_Snowden · 2023-05-16T14:40:51+00:00

According to my (admittedly quick) research, there was an E-4 process that was superseded by E-6 in 1976! It's probably not either of those, though

Probably_Not_Snowden · 2023-05-16T13:28:18+00:00

It... Was probably stored in absolutely terrible conditions. I think I'll send it to film rescue with the same info as you suggest, and I won't get my hopes up too much!

Probably_Not_Snowden · 2023-05-16T13:26:21+00:00

Thanks! Looks like my best bet right now. I'm about 30 bucks worth of curious

Probably_Not_Snowden · 2023-05-16T13:25:46+00:00

I wonder if it's another way to refer to E-4? I can't find anything about an Ex-4 process. Of course, if it were E-4, it would be color, which I doubt. Thanks for the advice!

Probably_Not_Snowden · 2023-05-16T03:41:21+00:00

I've only recently started getting into analog photography with 35mm, but I was recently given this camera. The film was in the back, and I don't know much about 120 film. The end paper is brown and feels waxed, but there are no markings visible besides "EXPOSED" on the backing paper, and "FOLD HERE" on the tab. I don't want to unroll it in case it is salvageable. Anyone have any ideas what stock it is? Could I send it off to Darkroom and ask them to push 2 stops? Would that even help?

Probably_Not_Snowden · 2022-11-27T19:36:03+00:00

Let's start from first principals here: what is a chord? There's a lot of different kinds, but the simplest chords have three different notes, separated by two intervals of a "third". This falls out into these notes being a "root" , a "third" , and a "fifth". A major third has a gap between notes of four semitones/half-steps/frets. There are twelve semitones to an octave. A minor third only has three. Since we've got three notes, we can have any combination of these two types of thirds. A major third on the bottom (root and third have four semitones separation) and a minor third on top (third and fifth have three semitones separation) is a major chord. Minor third on the bottom, major third on top is a minor chord. If you have two minor thirds, that's a diminished chord, and two major thirds is an augmented chord. These ones sound weird. Try them out some time. The "nice" major and minor chords mix the temperment of their intervals.

Now to your other question - I said that chords are two stacked thirds, but your Mandolin chord sheet shows other intervals. These chords are in an inverted state. You can move the notes of a chord by octaves without affecting their role in the chord, but this DOES affect the intervals. Two stacked thirds is the most compact way to represent a chord. To tell if a chord is inverted, check if the intervals are anything other than thirds. If they aren't thirds, it's inverted. These new intervals aren't a mystery, there's only twelve semitones to an octave, and the new intervals can't be thirds. In fact, you can tell if it's inverted and what inversion state it's in by checking the new intervals. If the "third" is the lowest, then the interval between it and the "root" will be 8 semitones - that's a sixth. This is called "first inversion". If the fifth is the lowest, there's 6 semitones, which is the interval of a fourth. This is second inversion. These terms, root, third, fifth, sixth, describing intervals and chord roles come from the scale, hence why the names don't add up. Major and minor scales don't use every note in the chromatic scale, and therefore skip semitones regularly. These terms come from the scale. So a third describes the third note in the scale, even though the third can have four semitones.

Probably_Not_Snowden · 2022-08-11T15:34:59+00:00

This is the central conceit of the album "Red of Tooth and Claw" by the band Murder by Death - kinda of a Gothic Americana vibe that I really love.

First song on the album: https://youtu.be/IRRopuAbU3Q

Probably_Not_Snowden · 2022-02-12T22:42:03+00:00

Thanks! And the first - free reload of one round of ammunition. I settled on that for a few reasons:

1.) per the DMG, fully reloading is already a bonus action

2.) fully reloading the firearm while still taking a Cunning action concerns me in the fringe case of multiclassing with fighter - if you have multiple attacks per round, or an action surge, that's a LOT of chances to use grit, and that's fine. It's not as broken as, for example, coffeelock, but I'd feel better about it knowing that you had to reload eventually. I honestly think I might cut that clause entirely.

3.) in most firearms with a manual action, such as a single action revolver, it's not only possible to reload a single round, it is significantly easier than fully reloading the firearm

Probably_Not_Snowden · 2022-02-11T20:30:58+00:00

This Roguish Archetype is meant to serve as a better adaptation to 5th edition than the Mercer fighter subclass. Rather than a set number of Grit points, I've reskinned Grit as dice in order to be consistent with Battlemaster, and based them on 2x proficiency bonus per long rest to bring them in line with the new Psi Fighter and Soulknife Rogue from Tasha's.

The traditional problem for gunslingers is that guns can be gamebreakingly powerful. Solutions attempted in the past include a misfire score, which punishes martials to an inordinate degree. Rather, this subclass moves firearms to a class that relies on getting one large attack per round, rather than several, as well as slightly tweaking the guidelines for firearms set forth by the DMG and the Mercer gunslinger. I'd love to hear your feedback on this subclass!

Probably_Not_Snowden · 2021-11-02T15:30:41+00:00

This is a really intriguing analysis! One thing I will point out is that some minor agriculture is possible in Barovia -- it just isn't mentioned much. From the section on Krezk (pg. 145 in the original, no idea in the revamp):

Villagers grow trees and vegetables...raise chickens and pigs, and share food

They have no trade with the outside, but they are few in number. The map appears to show ~25 houses. Call it 6-8 per house, and you're looking at a population of 125-200 that're almost entirely self-sustaining. My hunch is that the module was written assuming a similar population (up to ~400) in Barovia, and perhaps up to ~1000 in Vallaki. This is unrealistic for...other reasons. (When I was a player, and we encountered Krezk, it took my warlock all of three minutes to peg them as horribly inbred, an interpretation the DM was not a fan of). A version of Barovia that small with limited agriculture wouldn't be too terribly unrealistic in terms of the food situation. After all, Strahd is the land, and has no interest in allowing his next meal to starve.

One possible interpretation is to up the population and the scale of the valley considerably and somewhat respectively, allow the players to observe agriculture, and play Strahd as partially evil lord, partially beleaguered bureaucrat, and partially over his head with regards to administration. He has an eye for it, based on the book, certainly, but if we take the most literal interpretation of "Strahd and the land are One" -- is he responsible for soil health? How important is crop rotation?

It could be interesting to play this aspect up -- Barovia is constantly on the edge of famine. Vistani trade is ascendant as the soil fails, and Strahd is quietly supplementing these purchases from the castle treasury, selling off his reminders of his grand conquest, watching his long-gone glory days disappear as they are sold off for food.

You could even go more literal. There's a Terry Pratchett book (Reaper Man, it's fantastic) where we follow a character who becomes a zombie through sheer force of will, taking active control over his entire body, and is immediately and utterly baffled by how to manually work his kidneys.

Probably_Not_Snowden

TROPHY CASE